How to not break water pump bolts?

Had a nice drive in the '67 CJ5 today in Santa Barbara's back country. The Dauntless V6 ran great. Back on the pavement we stopped to unlock the hubs and noticed a small spot of coolant on the ground. It looks like it is leaking at one of the water pump bolts. I thought, "That looks simple enough. I'll just drain the coolant, unbolt the water pump, replace a gasket, and be back in business." But first I logged on here to see if there might be more involved. I'm glad I did! After doing a search on "water pump" and reading the posts I'm almost afraid to put a wrench on the bolts. It sounds like it's very common to break the bolts holding the water pump on. Maybe I'll be lucky and the guy who installed the water pump put anti-seize on the threads. But maybe not. I read the posts suggesting using an acetylene torch to loosen stuck bolts. But that's probably not the best place to start. I have have had good results using a pneumatic impact wrench to take apart rusted/frozen through-bolts with nuts on the other end. I haven't had one break yet. But in those situations there was no down-side if the bolt did break. Would you recommend using a pneumatic impact wrench from the get-go to try to back off the water pump bolts, instead of a regular hand wrench or socket? Any other suggestions on the best way to get these bolts out without breaking them?
Thanks.

 

I learned the importance of anti-seize....

What I did was used a propane torch, I don't have a acetylene torch. I did break a few bolts, never tried impact wrench. The problem is a few of the bolts are about 6 inches. So things like using candle wax, didn't work for me. I held the propane torch on the bolt for a few minutes, then tried.

 

Yes, I'm afraid these are a problem sometimes. As piffey263 pointed out, the bolts that usually break are the long ones and using heat as a preventative isn't too effective because of that length.

I think your idea of trying an impact wrench may be as good as any to break the corrrosion that may be cementing the threads into the holes. Unfortunately when these break they usually break off flush with the hole in the timing cover. It's even more unfortunate that the thermal conduction properties of the aluminum material make the use of heat problematic to remove a broken off stub.

I have had success in drilling out a broken bolt out of one of the blind holes in a 225 timing cover. I did remove the timing cover from the engine so I could get it on the drill press table. I would never have been able to hand drill the hole accurately enough to save the threads in the hole. The key to success in saving this one was accurately marking center of the bolt, then drilling to just under the minor diameter of the threads. Then is when I used the heat to soften the steel left in the hole, then I used a sharp prick punch begin to 'pick' the spiral of steel out of the first couple turns of the threads. With that as a starting point, a tap removed the rest.

Good luck, I hope the impact tool saves you all the trouble. Or, maybe a PO did use anti-sieze.

Don

 

I like to work them back and forth. Patience is your friend. A few minutes a bolt to work them loose beats drilling and re-tapping holes any day. An impact tends to just break them off. Welding a nut onto the broken off remnant with a wire feed welder is usually the easiest extraction method. As many have found out the hard way, anti-seize is one of the most important things to have when working on old iron.

 

A long bolt is going to twist and reduce the effect at the threaded part, impact wrench or by hand.

I'd suggest applying repeated direct in-line impact/shock to break them free before torquing.

 

I must have been lucky on my 48. Didn't give me any problems. All came right out like they wanted a new pump and gasket for no reason.

 

So, I just found the time today to pull the water pump. But after all of my concern about possibly breaking off bolts, I found that the bolt where coolant was leaking was just more than finger tight. The coolant appeared to be leaking out of the bolt hole, and not from the gasket seam. So I am considering whether I should just reinsert the bolt and tighten it to stop the leak. It is one of the long bolts, at about 7 o'clock when you look at the water pump from the front. Question - "Does the bolt hole bottom out, or does it go clear through into some coolant filled cavity?" In other words, is the gasket leaking, or do the threads also have to be sealed to prevent leaking? There is no lock washer, so should I use some lock-tite on the threads so it doesn't vibrate loose, or should I use some anti-seize to make future removal easier?

Thanks for your advice.

 

I can't answer about where the coolant's coming from, but I'd suggest antisieze and NOT Locktite! I'd also recommend a new bolt if possible, rather than re-using an old one. JMHO.